Creation and Validation of a Proteome-Wide Yeast Library for Protein Detection and Analysis

A significant challenge in cell biology is to uncover the function of uncharacterized proteins. Surprisingly a quarter of the proteome is still poorly understood even in the most well studied model organisms. Systematic methodologies, including the use of tagged protein collections, have emerged as a powerful approach to address this gap. Despite the availability of proteome- wide collections featuring various fused proteins, the impact of tag size on protein function highlighted the need for using minimally disruptive tags for functional genomic studies. To rise to this challenge, we have created a proteome-wide collection of yeast strains in which proteins are N-terminally tagged with the Hemagglutinin (HA) epitope. The library leverages the compact size of the HA tag to minimize drawbacks associated with larger tags while enabling efficient functional analysis. We showcase the potential uses of our library for systematically evaluating protein size, abundance and localization using an in vivo labeling approach. Our characterization underscores the potential utility of a proteome-wide HA-tagged library in revealing novel aspects of cell biology, providing an additional powerful tool for functional genomics.